Programmers? Quite possibly, yes
Software Developers? No, absolutely not

And most programmers worth their salt would be able to take up a job or at least start becoming software developers themselves.

In the far future, maybe Codex would replace all programmers, but all the programmers that were being replaced took up jobs as Software Developer, Game Developer, Project Manager, and all other high-lever IT jobs.

Projects that were once impossible for one person becomes possible. Regular programmers suddenly has more chance of becoming a software developer or even build their own startups.

Not to mention that positions such as Cloud Engineers are always necessary to maintain any system under the sun.

So yeah, the job programmers might be threatened, but the people in it will prosper.

(Unless, of course, you somehow build a career of being a Programmer without ever learning about the fundamentals of Software Development, in which case... Tough luck baby, natural selection!)